[Python-ideas] [Python-Dev] hello, new dict addition for new eve ? (original) (raw)

Terry Reedy tjreedy at udel.edu
Tue Jan 3 22:02:04 CET 2012

On 1/3/2012 11:59 AM, Nathan Rice wrote:

This is slightly tangential, but I've always wondered... Why aren't set operations implemented on dicts? It is fairly natural to view a dictionary as a set of (key, value) pairs. Things like subset/superset checking (with concomitant operator support) make sense. I have written stuff like set(dict1.items())< set(dict2.items()) many times.

As a said earlier in this thread, being able to view dicts as sets is such a good idea that it was already added a few years ago.

{1:1}.items() < {1:1, 2:2}.items() True

I don't even know what rich comparison operators on dictionaries do now, it isn't intuitive at all.

TypeError: unorderable types: dict() < dict()

-- Terry Jan Reedy

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